1. Field of the Invention
The present invention relates to a device for the harvesting of nuts, and in particular to improvements in devices for separating and lifting the accompanying debris from the nuts during harvesting.
2. Description of the Prior Art
A great obstacle to the successful harvest of a crop, such as pecan nuts, is the gleaning and gathering of nuts that have fallen to the ground. These fallen nuts intermix with assorted ground debris and litter. Many mechanical nut pickers have been proposed in the prior art to collect the nuts while separating out the debris and litter.
U.S. Pat. No. 5,001,893 issued to Stanley et al. on Mar. 26, 1991 describes a tractor-driven harvester which uses a suction fan mounted at the center front end of the harvester. Air is drawn in through a debris separation chamber. Both the air and debris are forced through a vacuum chamber and discharged through an exhaust opening.
U.S. Pat. No. 4,982,559 issued to Calais on Jan. 8, 1985 describes a harvester which gathers nuts without using conveyers or blowers. Nuts are swept from the ground into the harvester by a rotary drum with flexible tines that sweep the ground. Debris is separated by a brush barrier as the nuts are swept in the harvester.
French Patent No. 2 631 515 issued to Armengol et al. on Nov. 24, 1989 describes a fruit harvester machine wherein a rotary brush sweeps the ground and propels fruit and attendant debris into the machine. A sieve then separates the fruit from the
U.S. Pat. No. 4,524,573 issued to Kinney on Jun. 25, 1985 describes a harvester using positive air pressure to eject the gathered berries from rotating vacuum fingers to a conveyer.
U.S. Pat. No. 3,872,657 issued to Ramacher et al. on Mar. 25, 1975 describes a harvester using a stream of air to assist in lifting lighter debris from a conveyer belt. The nuts are dropped in a separator housing. The air stream is made to move upwardly in the separator housing to carry the remaining debris away as the nuts fall. The air streams are created by the same fan. The first air stream is created by the negative pressure of the fan, and the second air stream is created by the positive pressure of the fan. A flexible damper may be used to-regulate the air flow to the fan.
U.S. Pat. No. 3,862,538 issued to Henson on Jan. 28, 1975 describes a harvester using an axial flow of air to remove the lighter debris from the nuts as they move from a conveyor belt to a collector bin. The debris is discharged through an exhaust duct.
U.S. Pat. No. 3,789,592 issued to the present inventor on Feb. 5, 1974 describes a self-propelled harvesting machine using a blower to remove the lighter debris from the heavier nuts as they are moved along a conveyor belt.
U.S. Pat. No. 3,591,948 issued to Brumbaugh on Jul. 13, 1971 describes a harvester in which the nuts and debris are moved along an arcuate path through an upwardly directed stream of air in a rotating perforated cylinder. Another air stream carries the debris laterally out of the open end of the cylinder.
U.S. Pat. No. 3,475,889 issued to Overstreet et al. on Nov. 4, 1969 describes a harvester where a fan blows air across the space where nuts and debris are thrown by the fingers of a rotating flipping mechanism. The nuts and some remaining debris land on a conveyer belt. Additional fans below the conveyer belt then blow the remaining debris away as the nuts are carried away and back.
U.S. Pat. No. 3,182,437 issued to Ramacher et al. on May 11, 1965 describes a harvester using a stream of air to assist in lifting lighter nuts from heavier debris off a conveyer belt. The nuts are transported with the air flow to a vertical separator where the nuts then swirl down to a conveyer.
None of the above patent references, either alone or in combination, is seen to describe the instant invention as claimed. While these and other patents disclose the use of a blower to help separate nuts and other crops from the debris in a harvesting machine, these prior art harvesters can be rather bulky and difficult to maneuver in small areas. In addition, the known prior art does not disclose or suggest the use of two converging and nonparallel air streams to separate the chaff from the nuts.